Fiber Optic Sensing of Fluorescent Emission from Compressed Cyanine-Dye-Impregnated Fatty Acid Monolayers at the Air/Water Interface

1988 ◽  
Vol 42 (4) ◽  
pp. 605-608 ◽  
Author(s):  
W. M. Reichert ◽  
C. J. Bruckner ◽  
Sui-Ren Wan
Keyword(s):  
Fatty Acid ◽  
Fiber Optics ◽  
Fiber Optic ◽  
Arachidic Acid ◽  
Cyanine Dye ◽  
Water Interface ◽  
Molecular Area ◽  
Molar Ratios ◽  
Langmuir Film Balance ◽  
Air Water Interface

Fluorescence was collected from cyanine-dye-impregnated arachidic acid monolayers at the air/water interface with the use of a fiber optics configuration and a Langmuir film balance. Fatty-acid-to-dye molar ratios in the monolayers ranged from 99:1 to 1:1. The monolayers were compressed in a step-wise manner, with sampling of cyanine fluorescence after each compression step. A drop in fluorescence intensity ranging from 20 to 80% was observed between the uncompressed and compressed monolayers. The observed fluorescence decrease appeared to be a function of barrier pressure rather than molecular area and dye concentration.

Metastability in Monolayer Films Transferred onto Solid Substrates by the Langmuir-Blodgett Method: IR Evidence for Transfer-Induced Phase Transitions

1994 ◽  
Vol 48 (10) ◽  
pp. 1196-1203 ◽  
Author(s):  
Fazale R. Rana ◽  
Suci Widayati ◽  
Brian W. Gregory ◽  
Richard A. Dluhy
Keyword(s):  
Fatty Acid ◽  
Conformational Changes ◽  
Structural Changes ◽  
High Surface ◽  
Solid Substrate ◽  
Water Interface ◽  
Monolayer Films ◽  
Langmuir Blodgett ◽  
Monomolecular Film ◽  
Air Water Interface

The rate at which a monomolecular film is deposited onto a solid substrate in the Langmuir-Blodgett process of preparing supported monolayer films influences the final structure of the transferred film. Attenuated total reflectance infrared spectroscopic studies of monolayers transferred to germanium substrates show that the speed at which the substrate is drawn through the air/water interface influences the final conformation in the hydrocarbon chains of amphiphilic film molecules. This transfer-induced effect is especially evident when the monolayer is transferred from the expanded region of surface-pressure-molecular-area isotherms at low surface pressures; the effect is minimized when the film molecules are transferred from condensed phases at high surface pressures. This phenomenon has been observed for both a fatty acid and a phospholipid, which suggests that these conformational changes may occur in a variety of hydrocarbon amphiphiles transferred from the air/water interface. This conformational ordering may be due to a kinetically limited phase transition taking place in the meniscus formed between the solid substrate and aqueous subphase. In addition, the results obtained for both the phospholipid and fatty acid suggest that the structure of the amphiphile may help determine the extent and nature of the transfer-speed-induced structural changes taking place in the monomolecular film.

BEHAVIOR OF METHYLENE BLUE WITH ARACHIDIC ACID IN THE RESTRICTED GEOMETRY OF LANGMUIR–BLODGETT FILM

2014 ◽  
Vol 21 (02) ◽  
pp. 1450030
Author(s):  
INDRA GHOSH ◽  
AJITESH PAL ◽  
JAYASREE NATH ◽  
BIJAY KUMAR MISHRA ◽  
RANENDU KUMAR NATH
Keyword(s):  
Methylene Blue ◽  
Quartz Substrate ◽  
Arachidic Acid ◽  
Layer By Layer ◽  
Water Interface ◽  
Restricted Geometry ◽  
Langmuir Blodgett ◽  
Isotherm Study ◽  
Air Water Interface ◽  
Interaction Kinetics

Anti-malarial methylene blue (MB) doped in arachidic acid (AA) have been incorporated in the Langmuir monolayer at the air–water interface and also in the Langmuir–Blodgett films deposited on quartz substrate. The pressure–area (π–A) isotherm studies at different concentrations of MB pointed out that pure MB could not form stable monolayer at the air–water interface and collapse readily at very low surface pressures. However, mixture of MB with AA formed stable monolayers and they could be transferred into solid quartz substrate to form mono/multi layered films of MB. The area per molecule of floating mixed monolayers was systematically decreased with the increasing concentrations of MB in the mixture. The pressure–time (π - t) isotherm study indicated the interaction kinetics between MB and AA. Higher the concentration of MB, higher is the increase in pressure. The spectroscopic characteristics of the mixed LB films have been compared with that of pure MB solution, microcrystal and layer-by-layer self assembled film with UV-Vis absorption spectroscopy. Surface morphology of the mixed LB and LbL film of MB was measured with atomic force microscopy (AFM).

scholarly journals Mechanistic Insights on the Photosensitized Chemistry of a Fatty Acid at the Air/Water Interface

2016 ◽  
Vol 50 (20) ◽  
pp. 11041-11048 ◽  
Author(s):  
Liselotte Tinel ◽  
Stéphanie Rossignol ◽  
Angelica Bianco ◽  
Monica Passananti ◽  
Sébastien Perrier ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Water Interface ◽  
Air Water Interface

Atmospheric photochemistry at a fatty acid-coated air-water interface

Science ◽  
2016 ◽  
Vol 353 (6300) ◽  
pp. 699-702 ◽  
Author(s):  
S. Rossignol ◽  
L. Tinel ◽  
A. Bianco ◽  
M. Passananti ◽  
M. Brigante ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Water Interface ◽  
Atmospheric Photochemistry ◽  
Air Water Interface

Study of an Imidazole Derivative Mixed with Fatty Acid at Air-Water Interface and in Ultrathin Films

2018 ◽  
Vol 5 (1) ◽  
pp. 2287-2294
Author(s):  
Bapi Dey ◽  
P. Debnath ◽  
D. Bhattacharjee ◽  
S. Majumdar ◽  
Syed Arshad Hussain
Keyword(s):  
Fatty Acid ◽  
Ultrathin Films ◽  
Imidazole Derivative ◽  
Water Interface ◽  
Air Water Interface

Phosphocholine reverses inhibition of pulmonary surfactant adsorption caused by C-reactive protein

1995 ◽  
Vol 269 (4) ◽  
pp. L492-L497 ◽  
Author(s):  
T. M. McEachren ◽  
K. M. Keough
Keyword(s):  
Pulmonary Surfactant ◽  
Water Soluble ◽  
Molar Ratio ◽  
Surfactant Adsorption ◽  
Dependent Manner ◽  
Water Interface ◽  
C Reactive Protein ◽  
Molar Ratios ◽  
Reactive Protein ◽  
Air Water Interface

The influence of the acute inflammatory phase protein human C-reactive protein (CRP) on the adsorption of porcine pulmonary surfactant from a subphase into an air-water interface has been investigated. CRP was shown to detract from the ability of surfactant to rapidly adsorb to the air-water interface at a molar ratio of 0.03:1 (protein:phospholipid) (weight ratio, 0.5:1). On a weight basis, CRP was found to be more effective than fibrinogen at reducing the adsorption rate of surfactant. The effect of CRP required the presence of calcium and was reversed by the addition of phosphocholine in a concentration-dependent manner. The inhibition of surfactant adsorption by CRP was effectively eliminated by the addition of phosphocholine at a molar ratio of 300:1 (phosphocholine:CRP), but it was not diminished by the addition of identical molar ratios of o-phosphoethanolamine or DL-alpha-glycerophosphate at the same molar ratios. These data suggest that the potent inhibition of surfactant adsorption by CRP is primarily a result of a specific interaction between CRP and the phosphocholine headgroup of surfactant lipids in the subphase and that it can be reversed by the water-soluble CRP ligand, phosphocholine.

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